Watchcase



Dec. 20, 1966 H. u. KLINGENBERG ,2

WATCHCASE Filed April 50, 1965 Attorney United States Patent M 3,292,362WATCHCASE Hans Ulrich Klingenberg, St. Niklaus, near Merzligen,Switzerland Filed Apr. 30, 1965, Ser. No. 452,240 Claims priority,application Switzerland, May 1, 1964, 5,719/ 64 Claims. (Cl. 58-91) Thisinvention relates to watchcases and in particular to watchcases havingtwo sections removably fixed together by means of a snap fit.

With the known watchcases of this type each watchcase section comprisesa slightly truncated conical annular surface and a fiat annular shoulderadjacent to the truncated conical surface. The truncated conicalsurfaces of both watchcase sections are adapted to each other in such away that they come into mutual engagement upon a slight elasticaldeformation of at least one of said sections and remain gripped to eachother due to the resistance opposed to a deformation by the material ofthe watchcase sections. Fixing devices by means of such a snap fit arecommonly used in the practice for securing for instance a bezel, abottom, a watch movement or an enlargement ring to a case-band or aglass to a bezel. They are excessively simple, easy to manufacture, safeand permit aesthetical pieces to be conceived and made. They cannot,however, be used when the watchcase sections are made of a materialwhich is so hard that it allows no noticeable elastical deformation.Thus, sapphire glasses could hardly be snap fitted correctly towatchcases made of steel. The same difiiculty also arises when anothersection of the watchcase is made of a very hard material such as acrystalline, ceramic or sintered material.

It is therefore an object of the invention to provide a watchcase withsnap fitting means which can also be used when one section of thewatchcase is so hard that it cannot be deformed elastically in anoticeable way.

A more specific object of the invention consists in providing awatchcase with an elastically yieldable ring having a truncated conicalsurface portion and fixed to one of said watchcase sections, and anannular surface portion located on the other watchcase section andhaving a shape adapted to the truncated conical surface portion of saidone watchcase section for constituting a snap fit herewith.

Still further objects of the invention will become apparent in thecourse of the following description.

One embodiment of the watchcase according to the invention isrepresented diagrammatically and by way of example in the accompanyingdrawings.

In the drawings, the single figure is .a part axial section of thewatchcase according to the invention.

The watchcase represented comprises a first section which constitutesthe case-band 1. This case-band 1 is circular and it is made in onepiece with a bottom part (not shown) constituting the watchcase bottomas well known to those skilled in the art. An annular groove 2 isprovided in the inner surface of case-band 1 for fixing a watch movementtherein by means of standard latching members. An annular cylindricalshoulder 3 having a flat bottom surface is also provided in the samecase-band surface and a plastic tightening gasket 4 of rectangularcross-section is located within shoulder 3. A sapphire glass 5 having afiat lower surface 6 is also placed within shoulder 3 so that the glassperiphery lies on gasket 4. The first watchcase section comprisingcaseband 1 and the glass thus fully enclose a space in which the watchmovement is located. The glass 5 is firmly retained within shoulder 3while pressing gasket 4 by the atmospheric pressure. For this purpose adepression 3,292,362 Patented Dec. 20, 1966 in a rounded edge 9. Aroundrib 7 the case-band further comprises an upper flat surface 10. Surface10 serves as abutting shoulder surface to a bezel 11 constituting asecond watchcase section removably fixed to the first watchcase sectioncomprising case-band 1. Bezel 11 constitutes a means which retains glass5 in place and prevents the same from falling out of its lodging if theair pressure accidentally increased in the watch movement space. Aninner bezel portion therefore extends over a chamferred peripheral area14 of glass 5. Bezel 11 is provided with an annular lodging 12 having acylindrical wall surface on the inside of bezel 11 and a flat bottomsurface adjacent to this cylindrical wall and forming an edge therewith.An annular ring 13 is soldered to bezel 11 in the edge of lodging 12. Asshown in the drawings ring 13 has substantially a rectangularcross-section and a truncated conical shape. The inner large surface ofring 13 has substantially the same opening angle as surface 8. A smallfree space thus remains between ring 13 and the cylindrical wall oflodging 12 so that the lower free por tion of ring 13 can yieldelastically in said space.

Bezel 11 and case-band 1 can both be made of a very hard material. Ring13 always permits the bezel to be removably fixed to the case-bandexactly in the same way as the bezel is snap fitted to the case-bandwith standard watchcases and this in spite of the fact that neithersecion 1 nor section 11 of the watchcase can yield to any noticeableextent.

Instead of soldering ring 13 in lodging 12 along one of its small sidesone could, in a modification, use a V- shaped and secure one of itsbranches against the cylin drical wall of lodging 12 for instance bysoldering, by gluing or in any similar manner.

With a further modification the bezel section of the watchcase couldalso have a portion surrounding the case-band. In this event this bezelsection would advantageously carry wrist-band attaching lugs.

With still another modification the watchcase could of course comprise aremovable bottom snap fitted to the case-band in exactly the same way asbezel 11 is snap fitted to case-band 1.

The watchcase according to the invention has not only the advantage thatall its parts can be made of very hard materials, but also that ofcomprising fixing means to secure the watchcase parts to each other,which are extremely simple and enable a safe and aesthetic assembling ofthe watchcase.

With still a further modification, ring 13 instead of being made of awell yieldable metal such as silvernickel or steel could also be made ofan elastically yieldable plastic such as hardened natural or syntheticrubber. This ring could thus be given an O-shape and the side wall oflodging 12 be accordingly made truncated conical.

It should finally be observed that the elastically yieldable ring of thewatchcase could also be secured to the corresponding watchcase sectionby heating this section, freely inserting the cold ring therein andcooling.

While the embodiment and different modifications have been describedhereabove, further modifications can obviously be resorted to by thoseskilled in the art without departing from or sacrificing the advantagesof the invention defined by the appended claims.

I claim:

1. In a watchcase having two relatively hard'rigid sections removablyfixed together by means of snap fit, in combination, an elasticallyyieldable ring having a truncated conical surface portion and beingformed of a separate piece from and fixed to one of said watchcasesections, the other watchcase section being provided with an annularsurface portion having a shape adapted to fit the truncated conicalsurface portion of said ring for constituting a snap fit therewith. I

2. In a watchcase according to claim 1, the annular surface portionprovided on said other watchcase sec-- tion being truncated conical.

3. ha watchcase according to claim 2, the truncated conical annularsurface portion provided on said other watchcase section and thetruncated conical surface portion of said elastically yieldable ringbeing parallel and engaging each other to constitute said snap fit.

4. In a watchcase according to claim 1, one section of the watchcaseconstituting a case-band and the other section constituting a bezel,said ring being fixed to said bezel.

5. In a watchcase having two relatively hard rigid sections removablyfixed together by means of a snap fit, in combination, an annularshoulder provided in one of said watchcase sections said shoulder havinga cylindrical Wall surface turned towards the inside of said onewatchcase section and a bottom surface forming an edge with saidcylindrical Wall surface, a truncated conical thin elastically yieldablering, of softer, more pliable material than said sections, having arectangular cross-section and being fixed along one of its small sidesto said one watchcase section in said edge of the shoulder thereof, andan annular surface portion provided on the other Watchcase section andhaving a shape adapted to fit said truncated conical ring forconstituting a snap fit therewith by cooperation with one of the largesurfaces thereof.

References Cited by the Examiner FOREIGN PATENTS 660,844 11/1951 GreatBritain. 249,165 6/ 1947 Switzerland.

RICHARD B. WILKINSON, Primary Examiner.

G. F. BAKER, Assistant Examiner.

1. IN A WATCHCASE HAVING TWO RELATIVELY HARD RIGID SECTIONS REMOVABLYFIXED TOGETHER BY MEANS OF SNAP FIT, IN COMBINATION, AN ELASTICALLYYIELDABLE RING HAVING A TRUNCATED CONICAL SURFACE PORTION AND BEINGFORMED OF A SEPARATE PIECE FROM AND FIXED TO ONE OF SAID WATCHCASESECTIONS, THE OUTER WATCHCASE SECTION BEING PROVIDED WITH AN ANNULARSURFACE PORTION HAVING A SHAPE ADAPTED TO FIT THE TRUNCATED CONICALSURFACE PORTION OF SAID RING FOR CONSTITUTING A SNAP FIT THEREWITH.